According to the first law of thermodynamics, if $Q$ is the heat added to a system and $W$ is the work done by the system, the change in internal energy is:

1. A $Q + W$
2. B $Q - W$ Correct answer
3. C $W - Q$
4. D $-Q - W$

Solution

$\Delta U = Q - W$ (with $W$ as work done by the system).

About this question

Subject: Physics · Chapter: Thermodynamics · Topic: Zeroth and First Law

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